Dental matrix for approximal fillings.



Ru 1 9 1 0 3 R m d m n .m a P.

J. G. HOLLINGSWORTH. DENTAL MATRIX FOR APPROXIMAL FILLINGS.

APPLICATION FILED SEPT. 8, 1914.

DENTAL M'ATRIX FOR APPROXIMAL FILLINGS.

Specification of Letters Patent.

Patented Manse, iois.

Application filed September 8, 1914. Serial No. 860,544.

To all whom it may concern.

Be it known that I, J EPTHA G. HoLLINes WORTH, a citizen of the United States, residing at Kansas City, in the county of Jackson and State of Missouri, have invented certain new and useful improvements in Dental Matrices for Approximal Fillings, of which the following is a specification.

This invention relates to a matrix for use by dentists in making approximal fillings,

and hasv for its object to produce means whereby a dentist without danger of cutting the patients gums is enabled to obtain accurate impressions of cavities and to make all kinds of approximal fillingssuch for instance as cast-inlay fillings; cold gold fillings whether produced outside the mouth-and then ceniented in the tooth cavity-as in the Hollingsworth appodonia method or system of filling teethor by the old method of plugging or tamping gold in the tooth; amalgam fillings, etc.

Another object is to produce a universal matrix in the sense that it can be used in approximal fillings of any character and is adjustable to accommodate teeth of any size and of either jaw.

To these ends the invention consists in certain novel and peculiar features of construction and arrangement of parts, as hereinafter described and claimed; and in order that the invention may be fully understood reference is to be had to the accompanying drawing, in which;

Figure 1, is an enlarged perspective View of a matrix embodying my invention. Fig. 2, is an enlarged perspective View showing the application of the matrix prior to and after the filling operation has been completed. Fig. 3, is a central vertical section of the construction shown in Fig. 2. Fig. 4:, is a section of the line IV-IV of Fig. 3.

In the said drawing the matrix is shown in the form of an extremely thin plate, and consists of a body portion 1, a head portion 2 and a narrow neck 3 connecting the head and bottom portions, the body portion being bent at its opposite sides to form a pair of wings 4. In practice the plate will preferably be made of steel of such thinness or gage that it can he slipped between the approximal cavity to be filled and the adjacent tooth, and is extremely ductile so that it can be bent in any way and retain the form to which it is bent.

Assuming that a tooth contains an approximal cavity-that is a cavity opening through the side of a tooth, adjacent an other toothand that itis desired to properly fill such cavity, the dentist after first preparing the cavity, slips the body portion of the matrix between the tooth containing the cavity and the adjacent tooth so that the wings shall bear against the tooth to be filled at opposite sides of the cavity therein. After the matrix has been arranged as explained, it is bent back transversely of its neck portion until the head portion 2, is pressed against the face or grinding surface of the adjoining tooth, so that the latter is utilized as an abutment, to prevent the matrix being driven sufiiciently far between the teeth to cut the gums. After the matrix has been arranged as explained, one or more wedges 5, or equivalent clamping means are forced between the back of the matrix and the said adjoining tooth, for the purpose of pressing and holding the matrix firmly against the tooth to be filled, it being preferable to insert the wedges from both the lingual or inner and the buccal or outer sides, as shown. The tooth is now ready to be filled with amalgam or other plastic filling or filling to be condensed in the cavity by pressure or tamping. If it is to be filled with a cast-inlay or by other hard filling prepared outside the mouth, an impression is taken with soft Wax or its equivalent and from such impression a mold or matrix is made and the filling prepared therefrom, as in cast inlays or by the method disclosed by the Patent #1,099,2 l8 issued to me on June 9, 1914, or any other suitable method, and such filling is cemented in the cavity.

By using a ductile matrix of the character described an accurate impression can be taken and the filling made and secured in place, or the filling can be made direct-as with plastic material or by tamping, as the head portion overlying the abutment tooth, will bend to accommodate necessary articulation between the abutment tooth and the opposing tooth of the other jaw, as will be readily understood by reference to Figs. 2 and 3.

Figs. 2, 3 and 4:, illustrate a matrix in operative position before the taking of an impression or the filling of a cavity and another matrix ready to be removed after the adjacent cavity has been filled, said figures fication without departure from the spirit and scope of the appended claim.

I claim:

A thin ductile matrix consisting of a body portion, a head portion and a narrow neck portion connecting the body portion and the head portion.

In testimony whereof, I aflix my signature, in the presence of two Witnesses.

JEITHA G- HOLLINGSWORTIL Witnesses FRANK R. GLOBE, G. Y. THORPE.

Copies of this patent may be obtained for five cents each, by addressing the Commissioner of Patents,

. Washington, D. C. 

